U.S. war veterans who sustained severe combat wounds and have chronic post-traumatic stress disorder (PTSD) are at increased risk for high blood pressure, a new study says.

The study included nearly 3,900 military veterans who had been severely wounded in Iraq or Afghanistan from February 2002 to February 2011. Their average age when they were wounded was 26.

More than 14 percent of the veterans developed high blood pressure at least 90 days after being wounded. The severity of the injuries and how frequently PTSD was noted in their medical records after the wounding separately affected their risk for high blood pressure.

“What we found surprised us,” said study senior author Dr. Ian Stewart, a major at the U.S. Air Force Medical Center at Travis Air Force Base in California.

For every 5-point increase on a 75-point injury severity score, the risk for high blood pressure rose 5 percent. Veterans with an injury severity score of 25 or lower and no recorded PTSD diagnosis had the lowest risk for high blood pressure, according to the study.

Compared with veterans with no PTSD diagnosis, the risk for high blood pressure was 85 percent higher among those who had PTSD noted one to 15 times in their medical records — indicating chronic PTSD.

High blood pressure was 114 percent more likely among veterans with PTSD noted more than 15 times, indicating a more severe condition, the study found.

Similar to previous research, the study also found that age, acute kidney injury and race also were associated with risk of high blood pressure. The risk rose about 5 percent for every year older a veteran was, and the risk was 69 percent higher among blacks than whites.

An injury to the kidneys, which play a key role in regulating blood pressure, also was linked to a higher risk for high blood pressure.

The findings were published March 19 in the journal Hypertension.

“PTSD does appear to increase the risk of hypertension, but we thought that hypertension risk from the injury would depend on the presence of PTSD,” Stewart explained in a journal news release. “Instead, increased hypertension risk is additive to the injury itself.”

Previous research has linked PTSD with high blood pressure, substance abuse, obesity, heart disease and suicide.

More information

The U.S. Department of Veterans Affairs has more on PTSD.